<!DOCTYPE html>
<html lang="en" xmlns:v-on="http://www.w3.org/1999/xhtml">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script src="https://cdn.jsdelivr.net/npm/vue/dist/vue.js"></script>
</head>
<body>
<div id="app">
    <h1>{{num}}</h1>
    <input type="text" v-model="num"/>
    <br>
    <button @click="stopClick">+</button>
    <button @click="num--">-</button>
    <h2>{{msg}}</h2>
</div>
<script type="text/javascript">
    var app = new Vue({
        el: "#app",
        data: {
            num:1,
            msg:"Hello World",
        },
        created(){
            this.msg="Goodbye vue";
        },
        methods:{
            stopClick(){
                console.log("stop click")
            }
        }
    });
</script>
</body>
</html>